Rail systems are used for a variety of different purposes. Passenger rail carries people over certain distances; freight rail transports goods and material from one location to another; and automated material handling systems (AMHS) transport a variety of different items or people around a particular industrial facility, such as a steel mill, microchip fabrication unit, or the like. Rail systems may often comprise mono-, dual-, or triple-rails, either configured on the ground, overhead, or a combination of both. Moreover, the rail cars may be configured to engage the rails at the top of the rail car, in which the rail car hangs below the rail, or at the bottom of the rail car, in which the rail car sits on top of the rail.
One consideration of the various rail systems is monitoring the conditions of the rails. Because most railroad car wheels physically contact the rail, rail damage and rail wear can sometimes cause rail failure, which, if not timely discovered, could lead to train derailment or the like. Derailment, whether for rail systems transporting people or goods, may cause catastrophic damage to goods, property, and the like, but may also cause loss of life for passengers or bystanders. In order to prevent such catastrophic failure, various systems and methods have been developed for inspecting rails.
A typical inspection system used to inspect railway tracks includes sensors, such as ultrasound sensors, eddy current sensors, and the like, that scan the tracks for known defect types, an analyzer to record and compile meaningful information from the scans, and data storage to store the analyzed information and/or the raw scan data. The sensors are generally placed in contact with or close proximity to the track/rail and are typically either attached to a wheel (or inspection wheel) that rolls over the track as the train moves or placed onto a carriage that attaches to the underside or some part of a train car close to the tracks.
Typically, such inspection systems require high resolution data. In order to obtain high resolution, the scan speeds are required to be substantially low such as 30 miles per hour. Such requirements impose a limitation on the train speed because as mentioned above, the sensors are typically mounted on the wheels or the undercarriage of the train. However, in order to perform real time inspection of the tracks, the inspection system is usually required to be implemented at higher speeds. A problem that often arises is that the obtained data resolution is significantly low as a result of higher speeds of operation. Data resolution is an important parameter for the accurate detection of flaws in railroad tracks.
Moreover, many modern rail systems, especially AHMS, include data transport mechanisms along the rail. Other rail systems include power transport, either over a separate rail, or some other related line. Most typical rail inspection systems test only the physical characteristics of the rail and leave monitoring of the additional data and power transport mechanisms to separate systems.
In AHMS systems used in industrial facilities, the current methods for maintaining the track system is to have plant management (PM) personnel manually/physically check the tracks. This manual process involves a great degree of manpower and loss of productivity when the rail system cannot be checked while the plant maintains normal operations. Moreover, in practice, manual inspection is conducted on more of a passive schedule, that is, when a problem is detected through some failure, correction and inspection is undertaken. Therefore, in many applications, the manual inspection does not typically prevent accidents or breakdowns, but only repairs such breakdowns or faults after the fact. Considering the manpower expended in manual inspection, the costs of maintaining the manpower and reacting to fault-events is very high.